The present invention relates to a process and an apparatus for uniformly distributing glass fibers onto a forming bed.
Apparatus and processes are known in the prior art for distributing glass fibers onto a forming bed of wet cementitious material, but these have many disadvantages owing to their method of distributing.
Glass fiber reinforcement can be incorporated into cementitious material in an interconnected random matrix by pre-mixing. However, in the pre-mixing method the physical act of pre-mixing tends to break down the matrix of the fibers thereby reducing the reinforcement of the overall cement product.
Another prior art method of dispersing the glass fibers utilizes a hand chopper and a hand sprayer for spraying the glass fibers onto a bed of cementitious material. This system also has the disadvantage of breaking down the fiber matrix and additionally has the disadvantage of not giving a uniform distribution of the glass fiber over a large bed area. Since this system is carried out by hand, it also has the disadvantage of not permitting an efficient way of handling the glass fiber reinforcement of materials on an assembly line basis.
A further known method utilizes the hand spraying of a mixture of glass and cement. Like other previous known methods, this system also breaks down the matrix of the fibers and also does not permit a uniform distribution of glass fibers nor is it convenient to use in a large scale operation.
In the glass fiber reinforcement of cementitious material, it is preferable to use as long a fiber as possible in order to provide greater reinforcement. In the known methods of distribution, the fibers must be short in order to carry out these methods and it is unusual for the fibers to be any longer than one inch in length. And thus this presents a distinct limitation to these types of distribution.